I love unique purses, like a lot, I'm making one out of a medical book, another out of an old radio, neck ties, candy wrappers, but I'm not sure how exactly to use the bottles as the metal is fairly thick. I dont know what sort of tool to cut it with or anything. I just want it to lay flat basically, I'm not too sure what to do after that but I think I can manage.

Metal saw is probably your best bet if it really is thick (I haven't seen the bottle myself). Saw off the top and the bottom, and saw it apart along one side, then bend it out with sturdy pliers and hammer it out from the back, on wood (hammering against metal will scratch it)Make sure your wood is on something immovable (anvil, slab of concrete, whatever you have), and that the wood isn't likely to move either - you don't want it to spring back too much.For assembly your best bet might be drilling holes along the edges and using a sturdy yarn to sew them together (I know you didn't ask for that part, but it popped into my head )

I agree with using a hack saw for the top and bottom (remember to saw against the teeth-direction of the saw, not back and forth, or you'll wreck the saw), but I'd use tin-snips to cut down the length of it cuz they're fast and easy for straight lines. And you oughtta beat it to death with a rubber mallet like what is used to take dents out of car panels, as a regular hammer may stretch the metal and mess up the paint-job.

On an aside, that's a darn COOOOOL idea! /files this away in her brain for later